JP3308346B2 - Air probe pin board for board inspection equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pin board comprising a support on which a plurality of probes are erected for a board inspection apparatus such as an in-circuit tester and a function tester.

[0002]

2. Description of the Related Art Conventionally, a mounting substrate, that is, a printed circuit board on which a large number of electronic components are soldered, uses an in-circuit tester, and the tip of a probe is brought into contact with each required measuring point on the substrate to perform electrical measurement of each component. Is used to determine the quality of the substrate. There are various types of such in-circuit testers. In the case of the press type, when performing measurement, a pin board 14 made of a resin support 12 having a plurality of probes 10 erected as inspection jigs as shown in FIG. Then, the mounting substrate 16 is placed on the pin board 14 and fixed by pressing in the direction of the arrow from above. Then, each probe 1
The reference numeral 0 denotes a contact pressure proportional to the stroke (retraction amount) of the electronic component mounted on the substrate 16 and a measurement point of a pattern or the like provided on the electrode, which is in contact with the measuring point of the electronic component mounted on the substrate 16. Connect to Each probe 10 includes, for example, a plunger 18, a barrel 20, a compression spring, a lead wire 22, and the like.
Since the spring force acts in the protruding direction (upward) by the compression spring housed in the inside of the barrel 0, the plunger 18 can slide inside the barrel 20. or,
When each probe 10 is erected, a through hole is opened at an appropriate position on the support 12 and inserted into the through hole and fixed.
The substrate 16 is fixed so as not to move in the horizontal direction.

[0003]

However, when such a pin board 14 with the probe 10 is used, if the measurement points on the substrate 16 have irregularities, the contact between the measurement points having the concave tip and the convex one is different. The stroke and the contact pressure of the same probe 10 change when the probe 10 comes into contact with the measurement point. Therefore, there is a problem that the contact resistance changes and the irregularities of the measurement point affect the measurement result. In addition, even when the substrate 16 is pressed and pressed against the tip of the probe 10, there is a case where the contact pressure is a static pressure, so that the flux film formed at the soldering position cannot be broken. Further, since the probe 10 has a complicated structure and a spring is built in the barrel 20, the outer shape becomes thick, and even if the probes are brought close to each other, it is impossible to cope with a fine pitch between measurement points.

The present invention has been made in view of such a conventional problem, and can cope with a fine pitch.
An object of the present invention is to provide an air probe pin board for a board inspection device which can easily break a flux film at a soldering point, can maintain a constant contact pressure regardless of unevenness of a measurement point on a board, and can easily obtain an accurate measurement result. I do.

[0005]

In order to achieve the above object, a support 28 having a plurality of air probes 26 erected thereon is used for an air probe pin board 24 for a substrate inspection apparatus according to the present invention. Each of the air probes 26 has a large-diameter portion 30 at the front end and a small-diameter portion 32 at the rear end, and a truncated cone-shaped stepped portion between the large-diameter portion 30 and the small-diameter portion 32. 38, and a plurality of air probes 26 that house an intermediate portion of each air probe 26 inside the support 28 using an elongated rod-shaped body provided with a stopper 34 that is larger than the diameter of the small diameter portion 32 at the rear end. An air chamber 52 having a common pipe connection hole 50 is provided, and the support 28 divided by the air chamber 52 is provided.
The large diameter portion insertion hole 48 having a diameter slightly larger than the large diameter portion 30 of each air probe 26 is provided on one side portion of the air probe 26, and the diameter slightly larger than the small diameter portion 32 of each air probe 26 is provided on the other side portion. The small-diameter portion insertion hole 54 having the

Alternatively, an air chamber 82 for accommodating an intermediate portion of each air probe 74 is provided inside a support 76, and these air chambers 82 are connected to air distribution holes 86 with pipe connection holes 84.
Connect through.

[0007]

An air chamber 52 having a pipe connection hole 50 common to a plurality of air probes 26 accommodating an intermediate portion of each air probe 26 is provided inside the support 28, and the air chamber 52 is formed by the air chamber 52. A large-diameter portion insertion hole 48 having a diameter slightly larger than the large-diameter portion 30 of each air probe 26 is provided on one side portion of the divided support member 28, and a small-diameter portion of each air probe 26 is formed on the other side portion. When the small-diameter-portion insertion holes 54 each having a diameter slightly larger than 32 are provided, compressed air is supplied from the pipe to the inside of the air chamber 52 through the connection hole 50, or is discharged from the air chamber 52 through the connection hole 50 through the pipe. it can.

Therefore, when the supplied compressed air fills the air chamber 52, compressed air pressure acts on the slope of the frustoconical stepped portion 38 formed between the large diameter portion 30 and the small diameter portion 32, and the large diameter The portion 30 and the small-diameter portion 32 slide inside the corresponding insertion holes 48 and 54, respectively, and quickly start projecting toward the distal end. Once the projection starts, the compressed air pressure acts directly on the area obtained by removing the cross-sectional area of the large-diameter portion 30 from the cross-sectional area of the small-diameter portion 32. In addition, the compressed air leaks to the atmosphere side from a small gap around the large diameter portion 30 and the small diameter portion 32, and the probe 26 floats up from the inner wall of the support member 28 to be in a non-contact state. Then, the sliding resistance becomes the shear resistance of the air layer, and has a negligible minute value. Therefore, if the substrate 70 to be inspected is set a little apart in the direction in which the air probes 26 protrude and is fixed, the tip of each air probe 26 can be brought into contact with a measurement point on the substrate 70. The contact pressure (static pressure) of each air probe 26 is determined by the supplied compressed air pressure regardless of the stroke based on the unevenness of the measurement point, and the collision pressure (dynamic pressure) at which the tip of each air probe 26 collides with the substrate 70 is used. ) Is determined by the flow rate of the compressed air. The maximum protrusion amount of each air probe 26 is determined by the stopper 3 provided at the rear end.
It is determined by the position of 4. When the air is exhausted from the air chamber 52, the suction action is exerted on the slope of the stepped portion 38, so that each air probe 26 retreats quickly.

Each air probe 7 is provided inside the support 76.
When the air chambers 82 for accommodating the intermediate portions of the air chambers 4 are provided, and these air chambers 82 are connected to each other through the air distribution holes 86 having the pipe connection holes 84, the area where the compressed air pressure acts is equal to each air chamber 82. Since the inner surface of the hole 86 becomes smaller, the mechanical strength increases.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a longitudinal sectional view showing an air probe pin board before measurement of an in-circuit tester to which the present invention is applied, and FIG. 2 is an enlarged view corresponding to a circle surrounded by a chain line.
In the figure, 24 is a pin board, 26 (26a, 26b, 26
c) is the air probe, and 28 is a resin support on which the air probe 26 is erected. Each of these air probes 26 is formed into a metal elongated rod-like body, a large-diameter portion 30 is formed at the front end and a small-diameter portion 32 is formed at the rear end, and the rear end has a thickness substantially equal to the diameter of the large-diameter portion 30. Is provided. Moreover, the end 36 of the large diameter portion 30 is formed in a conical shape, and the stepped portion 38 between the large diameter portion 30 and the small diameter portion 32 is chamfered to form a truncated cone. A lead wire (not shown) is connected to the stopper 34. In this manner, when each air probe 26 is formed into an elongated rod-like body, the tips can be brought close to each other, so that a fine pitch can be handled. The support 28 is composed of two rectangular flat plates 4.
0 and 42 are aligned up and down, and the predetermined positions of the ends are bolts 44 (44a and 44b) and nuts 46 (46a and 4a).
6b) and the like to form a single body. Incidentally, the upper and lower plates 40 and 42 may be bonded and bonded.

In the upper plate 40, a large-diameter portion insertion hole 48 which penetrates vertically into which the large-diameter portion 30 of each air probe 26 fits at a predetermined position in the center, and penetrates vertically to connect an external pipe. The one provided with each of the pipe connection holes 50 is used.
Further, the lower plate 42 has a recess 52 for an air reservoir which forms a main portion of an air chamber having a uniform depth reaching almost half of the plate thickness, which is wide on the upper surface of the central portion, and is provided at a predetermined position of the recess 52. Each air probe 26 is provided with a small-diameter portion insertion hole 54 vertically penetrated with the small-diameter portion 32 fitted therein. Moreover, the large-diameter portion insertion hole 48 has a slightly larger diameter than the large-diameter portion 30 of the air probe 26, and the small-diameter portion insertion hole 54 has the air probe 2.
6 is slightly larger in diameter than the small diameter portion 32. Then, as shown in FIG. 2, a gap of Δr, for example, 10 to 50 μm can be formed between the inner wall of the insertion hole 48 and the large diameter portion 30 and between the inner wall of the insertion hole 54 and the small diameter portion 32. . 56 (56a, 56b) is the upper and lower plates 40, 42
This is a dowel pin for accurately adjusting the position of.

In this manner, each air probe 26 is positioned at a predetermined position on the support 28 in which the upper and lower plates 40 and 42 are integrally connected.
Are mounted to form the pin board 24, and an air chamber 52 having a pipe connection hole 50 common to the three air probes 26 accommodating an intermediate portion of each air probe 26 is formed in the support 28 (air). The chamber is also given the same number as the air pocket recess). Therefore, the supply and exhaust piping as shown in FIG. 3 is connected to the piping connection hole 50 of the pin board 24. In the figure, reference numeral 58 denotes a pipe connection portion connected to the pipe connection hole 50;
0 is a compressed air source, 62 is a vacuum source, 64 is a three-port solenoid valve that switches between the piping from the compressed air source 60 and the piping from the vacuum source 62, and 66 and 68 are the compressed air sources 60.
, A pressure reducing valve and a speed control valve interposed in a pipe line from the to the three-port solenoid valve 64.

At the time of measurement, first, the substrate to be inspected 70 is set slightly apart from the pin board 24 in the direction in which the air probes 26 protrude, and fixed so as not to move in any direction. Then, the three-port solenoid valve 64 is energized. Then, the electromagnetic valve 64 is switched from the position shown in FIG. 3, and compressed air is supplied from the pipe through the connection hole 50 into the air chamber 52. When the room is filled, compressed air pressure acts on the slope of the frustoconical stepped portion 38, and the large-diameter portion 3 of each air probe 26.
0, the small-diameter portion 32 quickly starts to project in the corresponding insertion holes 48, 54 toward the distal end. Once the projection starts, the compressed air pressure acts directly on the area obtained by removing the cross-sectional area of the large-diameter portion 30 from the cross-sectional area of the small-diameter portion 32. In addition, since the probe 26 is in a non-contact state in which air leaks from the gap with the inner wall to the atmosphere side, the sliding resistance becomes the shear resistance of the air layer and has a negligible small value.

Then, as shown in FIG. 4, the tip of each air probe 26 can be brought into contact with a measurement point on the substrate 70. At this time, even if the measurement point has irregularities in the pattern or the soldering position and the stroke (projection amount) of each air probe 26 changes, the contact pressure (static pressure) is determined by the supplied compressed air pressure. If it is constant, the contact pressure will be constant. Therefore, the contact resistance is also constant, and the unevenness of the measurement point does not affect the measurement result. When the pressure reducing valve 66 is controlled, the contact pressure can be adjusted by changing the compressed air pressure. The collision pressure (dynamic pressure) at which the tip of each air probe 26 collides with the measurement point of the substrate 70 is determined by the flow rate of the compressed air. Besides,
By controlling the speed control valve 68, the collision pressure can be adjusted by changing the flow rate of the compressed air. Even if each air probe 26 projects without the substrate 70 to be inspected, its maximum stroke is determined by the position of the stopper 34 provided at the rear end as shown in FIG.

When the energization of the solenoid valve 64 is stopped after the measurement, the solenoid valve 64 returns to the position shown in FIG. 3 and the vacuum source 62 is connected to the connection hole 50 of the pin board 24 via a pipe. Air can be exhausted from the chamber 52 through the connection hole 50 and the piping. Then, since the pressure in the air chamber 54 becomes lower than the atmospheric pressure, the slope of the stepped portion 38 of each air probe 26 is sucked or the like, so that the air probe 26 quickly retreats to the position shown in FIG. In addition,
If the flux film is not broken through by a single collision with the measurement point of the air probe 26, the electric power to the solenoid valve 64 is repeatedly turned on and off, and good electrical contact is obtained by colliding several times.

FIG. 6 is a longitudinal sectional view showing another air probe pin board before measurement of the in-circuit tester to which the present invention is applied. In the figure, 72 is a pin board, 74 (74a,
Reference numerals 74b and 74c) denote air probes, and reference numeral 76 denotes a resin support made of upper and lower plates 78 and 80 in which the air probes 74 are erected at predetermined positions in the center. The pin board 72 is provided with air chambers 82 (82a, 82b, 82c) for accommodating intermediate portions of the respective air probes 74 inside the support 76, as compared with the pin board 24 of the above embodiment.
The difference is that these air chambers 82 are connected via an air distribution hole 86 having a pipe connection hole 84. However, other structures are almost the same.

FIG. 7 is a plan view showing a central portion 88 of an upper plate 78 constituting such a support 76, and FIG.
It is sectional drawing. The upper plate 78 has the same structure as the upper plate 40 of the above embodiment. In the figure, 90 (90a,... 90)
h) is a large diameter portion insertion hole through which the large diameter portion 92 of each air probe 74 is inserted. Incidentally, the large-diameter portion insertion hole 90 (90d,
90h), the corresponding large diameter portions 92 of the corresponding air probes 74 (74d,... 74h) are inserted. However, the air probe 74 (74d,... 74h) is not shown.

FIG. 9 is a plan view showing the central portion 94 of the lower plate 80 constituting such a support 76, and FIG.
It is a Y sectional view. The lower plate 80 is the lower plate 42 of the above embodiment.
With a different structure. In the figure, 96 (96a,... 9)
6h) is a small diameter part insertion hole through which the small diameter part 98 of each air probe 74 is inserted, and 100 is a pipe connection hole 84 on the upper surface of the lower plate 80.
This is a recess for air relay provided at the same position as that of FIG. The air relay recess 100 has a pipe connection hole 84 and an air distribution hole 86.
(86a, 86b) is a portion connecting the air distribution grooves, which are the main parts, and is made wider in a circular shape than each air distribution groove 86 (the air distribution grooves are also given the same numbers as the air distribution holes). Incidentally, the small-diameter portions 98 of the corresponding air probes 74 (74d,... 74h) are inserted into the small-diameter portion insertion holes 96 (96d,... 96h), and the air chambers 82 (82d,.
Correspond to the respective air probes 74 (74d,...).
74h) is stored. The air distribution holes 86a connect the three air chambers 82 (82a, 82b, 82c), and the air distribution holes 86b are connected to the five air chambers 82 (82d,...).
82h).

As described above, the air chambers 82 for accommodating the intermediate portions of the respective air probes 74 are provided inside the support 76, and the air chambers 82 are formed with the air relay recesses 100 having the pipe connection holes 84. When the connection is made via the air distribution holes 86 provided, the area on which the compressed air pressure acts is reduced by the inner surface of each air chamber 82, each air distribution hole 86, and the air relay recess 100, and the mechanical strength is increased. Therefore, the support 7
6 lower plate 80 can easily withstand the compressed air pressure.

[0020]

According to the present invention described above, claim 1
In the described invention, compressed air pressure is applied to the slope of the truncated conical stepped portion formed between the large diameter portion and the small diameter portion of each of the plurality of air probes, and the air probe is quickly protruded by smooth sliding. Can contact the measurement points on the substrate. Further, since the suction action is exerted on the slope of the truncated conical step portion of each air probe protruded by the exhaust, each air probe can be quickly retracted. Therefore, the inspection time can be reduced. Moreover, when each air probe is formed into a long and thin rod-like body, the tips can be brought close to each other at a close distance, and a fine pitch between measurements can be handled. If the flux film is not broken by a single collision with the air probe at the measurement point, the supply and exhaust of compressed air are repeated. can get. Also, since the contact pressure of each air probe is determined by the supplied compressed air pressure, regardless of the stroke based on the unevenness of the measurement point, if the compressed air pressure is constant, the contact resistance of each air probe will also be constant, and accurate measurement results Is obtained.

In the second aspect of the present invention, the area on which the compressed air pressure acts is small, so that the mechanical strength is large.
Since the support can easily withstand the compressed air pressure, the area of the air probe standing surface can be increased.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an air probe pin board before measurement of an in-circuit tester to which the present invention is applied.

FIG. 2 is an enlarged view corresponding to the inside of a dashed-dotted circle in FIG. 1;

FIG. 3 is a view showing supply and exhaust pipe paths connected to pipe connection holes of the air probe pin board.

FIG. 4 is a longitudinal sectional view showing the air probe pin board at the time of measurement by the in-circuit tester.

FIG. 5 is a vertical cross-sectional view showing a state in which the probe of the air probe pin board projects maximum when the substrate to be inspected is not installed.

FIG. 6 is a longitudinal sectional view showing another air probe pin board before measurement of the in-circuit tester to which the present invention is applied.

FIG. 7 is a plan view showing a central portion of an upper plate constituting a support of the air probe pin board.

FIG. 8 is a sectional view taken along line XX of FIG. 7;

FIG. 9 is a plan view showing a center portion of a lower plate constituting a support of the air probe pin board.

FIG. 10 is a sectional view taken along the line YY of FIG. 9;

FIG. 11 is a longitudinal sectional view showing a probe pin board at the time of measurement by a conventional in-circuit tester.

[Explanation of symbols]

24, 72 ... air probe pin board 26, 74 ... air probe 28, 76 ... support body 30, 92 ... large diameter part 32, 98 ... small diameter part 34 ... stopper 38 ... stepped part 40, 78 ... upper plate 42, 80 ... Lower plate 48, 90
... large-diameter portion insertion holes 50, 84 ... pipe connection holes 52, 82 ... air chambers 54,
Reference numeral 96: small-diameter portion insertion hole 58: connection portion of piping 60: compressed air source 62: vacuum source 64: 3-port solenoid valve 66: pressure reducing valve 68: speed control valve 70: substrate to be inspected
86 ... air distribution hole 100 ... air relay recess

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-234079 (JP, A) Japanese Utility Model Showa 49-7451 (JP, U) Japanese Utility Model Showa 62-203461 (JP, U) Japanese Utility Model Showa 63- 109657 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) G01R 1/06-1/073

Claims (2)

(57) [Claims] 1. An air probe pin board for a board inspection device comprising a support having a plurality of air probes erected thereon, wherein each of said air probes has a large diameter portion at the front end and a small diameter portion at the rear end. Between the large-diameter portion and the small-diameter portion to form a truncated cone-shaped stepped portion, using a long and narrow rod-shaped body provided with a stopper larger than the diameter of the small-diameter portion at the rear end, each inside the support A plurality of air probes accommodating an intermediate portion of the air probe are provided with an air chamber having a common pipe connection hole, and one side portion of the support divided by the air chamber is slightly larger than a large diameter portion of each air probe. An air probe pin for a board inspection device, wherein a large-diameter portion insertion hole having a diameter is provided, and a small-diameter portion insertion hole having a diameter slightly larger than the small diameter portion of each air probe is provided on the other side portion. board. 2. An air probe pin board for a board inspection device comprising a support having a plurality of air probes erected thereon, wherein each of the air probes has a large-diameter portion at the front end and a small-diameter portion at the rear end. Between the large-diameter portion and the small-diameter portion to form a truncated cone-shaped stepped portion, using a long and narrow rod-shaped body provided with a stopper larger than the diameter of the small-diameter portion at the rear end, each inside the support Air chambers for accommodating the intermediate portions of the air probes are provided, and these air chambers are connected via air distribution holes with pipe connection holes, and are provided on one side of the support divided by the air chambers. It is necessary to provide a large-diameter portion insertion hole having a diameter slightly larger than the large-diameter portion of each air probe, and to provide a small-diameter portion insertion hole having a diameter slightly larger than the small-diameter portion of each air probe on the other side portion. Features air pro for board inspection equipment Bubpin board.